Blue-green vat coloring-matter.



UNITED sirnrns Pnrnrir OFFICE.

HUGO WOLFE, OF MANNHEIM, GERMANY, ASSIGNOR TO BADISCHE ANILIN & SODA FABRIK, OF LUDWIGSHAFEN-ON-THE-RHINE, GERMANY, CORPORATION.

BLUE-GREEN VAT COLORING-MATTER.

No Drawing.

Specification of Letters Patent.

Patented Mar. 4, 1913.

2 '0 all whom it may concern:

Be it known that I, HUG-o lVoLrF, subject of the Grand Duke of Baden, residing at Mannheim, Germany, have invented new and useful Improvements in Blue-Green Vat Coloring-Matter, of which-the following is a specification.

By nitrating the niethyl-benzanthron having a melting point of 199 C. (which is de scribed rundown of a melting point of 243 C. can be obtained.

According to this invention mononitromethyl-benzanthron is heated'with sulfur whereby coloring matter is Obtained whichdyes cotton, from the vat, valuable blue-green shades.

The following jisan example of how my invention can be carried into practical efiect, but the invention is not confined to this example. The parts are by weight.

Mix well together methyl-benzanthron and 40 parts of sulfur, and heat the mixture at a temperature of in the specification of German Patout No. 200,335) a mononitro-methyl-ben--',

10 parts of mononitro'k from 220-240" C. until the evolution of sulfureted hydrogen ceases. When the melt is cold, powder it and extract with hot sodium sulfid solution, or with carbon bisulfid, in order to remove excess of sulfur. The coloring matter is a dark brown powder which can be made into a paste by dissolving it in conic'entrated sulfuric acid and then precipitating by means of Water. This yields a blue vat with alkaline hydrosulfite and the blue shades at first obtained on cotton from an impure state, it generally exhibits brown-red fluorescence in'nitrobenzene. In this example, the proportion of the ingredients and also the time and temperature of treatinent can be considerably varied withthis vat become, on washing and drying, fast blue-green shades. The pure dry coloring matter contains sulfur and isa darl r powder with a metallic luster and yields a brown-red solution in concentrated sulfuric acid and a dull violet solution in 23% fummg sulfuric acid. It is very difiicultly soluble in organic solvents. "When pure, it yields a green solution in nitrobenzene and can be recrystallized from this solvent. In a "cut departing from the nature of my invention. v

X ow what I claim is The new coloring matter which can be obtained by heating mononitro-methyl-benzanthi-on with sulfur, which coloring matter contains sulfur and consists, when dry, of a dark brown powder with a metallic luster, which yields a brown-red solution in concentrated sulfuric acid, a dull violet solution in 23% ifu'mins sulfuric acid a reen solution in nitrobenzene, and whith dyes cotton from the vat fast blue-green shades.

In testimony whereotI have hereunto'set my hand in the presence of two subscribing witnesses.

HUGO WOLFF.

Witnesses:

J. Anne. LLOYD, A. O. T'ITTMANN, 

